wait for futures when using restore worker

pfb/workers/restore.py

@@ -79,6 +79,7 @@ def _restore(**kw):
     from pfb.utils.restoration import restore_cube
     from itertools import cycle
     from daskms.fsspec_store import DaskMSStore
+    from distributed import wait
     try:
         from distributed import get_client
         client = get_client()
@@ -328,4 +329,7 @@ def _restore(**kw):
     #               hdr,
     #               overwrite=opts.overwrite)
 
+    if opts.nworkers > 1:
+        wait(futures)
+
     return